1. Field of the Invention
The present invention relates to a service verifying system for providing a plurality of services, an authentication requesting terminal to be authenticated by the service verifying system to utilize a service provided by the service verifying system, a service utilizing terminal for utilizing another service provided by the service verifying system on the basis of the result of the authentication of the authentication requesting terminal, and a service providing method.
2. Related Background Art
There are conventionally known systems for providing services for cell phones and PHSs in mobile communications and others. Each user needs to have a contract with a company providing services in order to utilize such services. Many of companies providing services provide services for only users having a contract for utilization of services (qualified users), but do not provide services for users without a contract. For this reason, it is necessary to establish a scheme for letting only the qualified users utilize the services, and schemes of this type have already been substantialized heretofore.
The existing service verifying systems for providing services employ a control system of managing customer information of qualified users, authenticating whether a user requesting utilization of a service is a qualified user, using the customer information, and permitting the utilization of the service only when the result of the authentication is affirmative. It is necessary to build up such a system, in order to let only the qualified users utilize the services.    [Nonpatent Document 1] Bruce Schneier, “APPLIED CRYPTOGRAPHY,” John Wiley & Sons, Inc., 1996, pp. 52-56    [Nonpatent Document 2] “NTT Docomo Technical Journal Vol. 9, No. 4,” The Telecommunications Association, January 2002, pp. 34-43    [Nonpatent Document 3] Keiji Tachikawa, “W-CDMA MOBILE COMMUNICATIONS SYSTEM,” John Wiley & Sons, Ltd, 2002, pp. 345-356